5 o6 SCIENCE PROGRESS 



The author divides the history of plant pathology into five eras — the ancient 

 era, extending from the earliest times to the fall of the Roman Empire (476 A.D.) ; 

 the dark or middle era, including the middle ages, and covering roughly the time 

 from the fall of the Roman Empire to the beginning of the seventeenth century; 

 the pre-modern era, extending from the beginning of the seventeenth to the middle 

 of the nineteenth century; the modern era, from about 1850 to 1906; and what 

 the author calls the present era, from 1906 onwards. It seems rather doubtful 

 whether the important events of the last twelve years are really such as to justify 

 the separation of this time from the modern era. The author bases this separation 

 on the following events : the establishment of chairs of plant pathology in 

 American universities ; Smith's work on crown gall ; the founding of the 

 American Phytopathological Society and its journal, Phytopathology ; the enact- 

 ment of the United States Quarantine Act of 1912 ; the introduction of sulphur in 

 place of copper fungicides ; the development of disease-resistant crops ; and the 

 outbreak of the chestnut blight in the Eastern United States. 



The four earlier eras are each divided by the author into periods, " phases in 

 the development and crystallization of the prevailing point of view of the epoch." 

 These periods are named after the men who are chiefly responsible for moulding 

 the thought of their respective periods. The resulting nomenclature strikes one 

 as being in some cases rather cumbrous, for, although " Kiihnian Period " and 

 " Ungerian Period'' are reasonable enough, the expressions " Zallingerian Period" 

 and " Millardetian Period" seem rather clumsy, and they are scarcely likely to 

 come into general use. 



The book consists very largely of biographies of those plant pathologists to 

 whose energies the development of the science is due. The style is clear and 

 readable, and the insertion of twenty-two portraits of eminent plant pathologists 

 adds to the interest of this little book. 



W. S. 



ZOOLOGY 



The Wonders of Instinct. By J. Henri Fabre. Translated by Alexander 

 Teixeira de Mattos and Bernard Miall. [Pp. 320, with 16 plates.] 

 (London : T. Fisher Unwin ; Toronto : The Musson Book Company, 1918. 

 Price io.y. 6d., or $3 net.) 



It is not often that one looks forward with pleasure to reviewing a scientific book, 

 as, although it may contain much of interest, yet there is almost invariably a great 

 deal that has to be read as a duty and sometimes a stern duty at that. The case 

 is entirely different with any further instalment of chapters translated from the 

 ten volumes of J. Henri Fabre's Souvenirs E?itomologique. The present volume 

 contains fourteen such chapters — two translated by Bernard Miall and the 

 remainder by Alexander Teixeira de Mattos — and is to be most cordially 

 recommended. 



The chapters are selected to illustrate various experiments conducted to 'test 

 the extent and limitations of the working of instinct in insects and the possibility 

 of the exercise of reason by these animals. No one can fail to be impressed by 

 the acuteness of the author in devising crucial tests to try the powers of the 

 insects, the patience shown in carrying out the experiments, and the typical Gallic 

 clearness with which the results are analysed and expressed. The results all 

 point in the same direction and show that, so far as can be discovered, instinct 

 alone governs the animals' activities. Although this is developed in some cases to 



